From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55B20C432C3 for ; Mon, 25 Nov 2019 11:38:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id EB2C420836 for ; Mon, 25 Nov 2019 11:38:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="aqveH8es" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EB2C420836 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 835146B05B5; Mon, 25 Nov 2019 06:38:36 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7E62F6B05C6; Mon, 25 Nov 2019 06:38:36 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 725BD6B05C9; Mon, 25 Nov 2019 06:38:36 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0036.hostedemail.com [216.40.44.36]) by kanga.kvack.org (Postfix) with ESMTP id 5D8D66B05B5 for ; Mon, 25 Nov 2019 06:38:36 -0500 (EST) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id F30C18249980 for ; Mon, 25 Nov 2019 11:38:35 +0000 (UTC) X-FDA: 76194602232.08.need07_8542103740960 X-HE-Tag: need07_8542103740960 X-Filterd-Recvd-Size: 3502 Received: from mail-io1-f67.google.com (mail-io1-f67.google.com [209.85.166.67]) by imf37.hostedemail.com (Postfix) with ESMTP for ; Mon, 25 Nov 2019 11:38:35 +0000 (UTC) Received: by mail-io1-f67.google.com with SMTP id p12so8463155iog.10 for ; Mon, 25 Nov 2019 03:38:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=xQjpj24zCEmZ7TaQMYF4URhsPWKFkVRBZHOy86dovGg=; b=aqveH8esNvZ3kcwzWN6CXW/lAHLjP6c9zgyU4CvcNf4LzoyMNL08gYJsR1KP8A7A3G ARjg3OUFxVZuqJMGQ7dvWA9uBcw9Q0Up4O6pivU+vbaWKONuXtb+dzZprJWvTOvu/4GI qWKaMpWRnTUKB4W8GzZQD8W7nhHZXbORaef4X+iVeFKSQKh9FI+3eiPIOb4s2KqhDlGr kWJo/gmrX6ve2ZcWtiNWw0CE/mfDINN7gP/gNGkX2DCZ7hxS/TG7rmOJn7xec1qd04c+ Vu8DVMOAz5itNVTFCTobEma0X+9rYNsqjSt1PZtyRnRg5sQRPHHsGrjGVP0FVXZ+Vlm4 Inog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=xQjpj24zCEmZ7TaQMYF4URhsPWKFkVRBZHOy86dovGg=; b=Vk0GPDD7e9ojE7NGoinVa5sC/wLyJYqKFUprm/lDdtlpIWZfauVOXS4VYSHSTReFe9 NT8hL9Uz+mdooJ4HUV88jgyNoYWfXlEeji9Z7RV2WHQ9H80y7K4ZY1CXzxfulMRPd76T H4TVKsk0GK4iHzWUGzu1mpoi4BNWn0GVVfZYq5h2pUmY0xJO4r2dbQDshUFB7DnOCHwz 2Ig0ScUEr5HzUfyyCwDGwQVDGBqUpP0K0959qpYVtdn0vn3xJk22GYaEqRgfTN4900E7 CKcNzq+mFBzlO8YCSr0um+4O7kOgKHw6pQs0FRinOhnlJ9EpluWMhMKNqsTZn4zY3oMP 2UUg== X-Gm-Message-State: APjAAAVEh40GJGFfZVgBXw8m3WabpzLS0bR/kdJ8RcANIt/d/9LS/5md PZ1crygE6slRNmo80qsMByaLQyYOTZ4IKg6iC3M= X-Google-Smtp-Source: APXvYqz/dj+HdaB1QN+WLjURAQ7dbOzIQ4ut1/nILxKcRYxuekSpwdszVDFxcTmePt4S0zOcUlFiMpDlxG3vsBmt6zI= X-Received: by 2002:a02:58c8:: with SMTP id f191mr26089339jab.94.1574681914986; Mon, 25 Nov 2019 03:38:34 -0800 (PST) MIME-Version: 1.0 References: <1574676893-1571-1-git-send-email-laoar.shao@gmail.com> <20191125110848.GH31714@dhcp22.suse.cz> In-Reply-To: <20191125110848.GH31714@dhcp22.suse.cz> From: Yafang Shao Date: Mon, 25 Nov 2019 19:37:59 +0800 Message-ID: Subject: Re: [PATCH] mm, memcg: clear page protection when memcg oom group happens To: Michal Hocko Cc: Johannes Weiner , Vladimir Davydov , Andrew Morton , Linux MM Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000655, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Nov 25, 2019 at 7:08 PM Michal Hocko wrote: > > On Mon 25-11-19 05:14:53, Yafang Shao wrote: > > We set memory.oom.group to make all processes in this memcg are killed by > > OOM killer to free more pages. In this case, it doesn't make sense to > > protect the pages with memroy.{min, low} again if they are set. > > I do not see why? What does group OOM killing has anything to do with > the reclaim protection? What is the actual problem you are trying to > solve? > The cgroup is treated as a indivisible workload when cgroup.oom.group is set and OOM killer is trying to kill a prcess in this cgroup. We set cgroup.oom.group is to guarantee the workload integrity, now that processes ara all killed, why keeps the page cache here? Thanks Yafang